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What should employers do to relieve heat stress?

An office worker uses an electric fan. Stock photo by Getty Images.

When the temperature and humidity is sweltering, it’s an appropriate time for employers to think about how to protect their workers from the effects of excessive heat.    

The body experiences heat stress when exposed to high temperatures for prolonged periods and when it’s combined with hard physical work, loss of fluids and fatigue. This can lead to fainting, heat rashes, heat exhaustion, heat strokes and even death. 

This may be caused by process heat or weather heat. Process heat is generated in the work environment by machines and equipment used for processing and creating the products. Think of commercial kitchens, bakeries, smelters and furnaces.

The majority of workplaces do not have hot processes, but some may require employees to work outside in hot weather.

Across all provinces, the law requires employers to take any reasonable precaution in the circumstances for the protection of workers. This is not limited to addressing obvious hazards such as slippery surfaces or defective machinery. The employers’ obligations extend to protecting employees from sweltering conditions in the workplace.

Provincial governments such as Ontario and British Columbia have posted guidelines for how employers can help alleviate the effects of heat stress and meet their legal obligations. These include:

  • Engineering tools: exhausting hot air and steam, creating air movement and providing cool, shaded work areas;
  • Administrative tools: assigning additional workers to slow the pace of work, increasing the number of breaks, providing cool drinking water and scheduling hard jobs for cooler times.

When it comes to process heat, the Ontario Ministry of Labour suggests the employer follow the American Conference of Governmental Industrial Hygienists (ACGIH) and set up a heat-stress control plan to ensure the employee’s core body temperature does not exceed 38 degrees Celsius.

Read more:

 Occupational Health and Safety Act Alberta

OHS Regulations & related materials British Columbia